Glomerular Filtration Rate Measurements Using 99mTechnetium-mercaptoacetyltriglycine Dynamic Renal Scintigraphy in Children with Renal Disease

PURPOSE: In children, 24-hour urine collections are unreliable for evaluating glomerular filtration rate (GFR) because of the difficulty of regulating voiding and the daily variation of urinary creatinine up to 25%. Additionally, creatinine clearance (Ccr) based on urinary creatinine is considered inaccurate. The purpose of this study was to compare estimated GFR determined using Ccr, formulas with serum cystatin C and creatinine, and 99mTc-mercaptoacetyltriglycine (MAG3) dynamic renal scintigraphy. METHODS: This retrospective study included 101 patients (age, <18 years) who visited Chung-Ang University Hospital between July 2011 and August 2012. GFR was estimated using 24-hour urinary creatinine, five formulas with serum creatinine and cystatin C, and 99mTc-MAG3 renal scan. RESULTS: Of the 101 patients, glomerular renal diseases were present in 60 patients (59.4%) and non-glomerular diseases were present in 41 patients (40.6%). There was a significant correlation between estimated GFR determined using 99mTc-MAG3 renal scan and Ccr (r=0.389, P<0.001). The correlation values between estimated GFR determined using 99mTc-MAG3 renal scan and each formula of Schwartz, Counahan-Barratt, Cockcroft-Gault, Filler and Lepage, and Bokencamp were 0.265 (P=0.007), 0.128 (P=0.044), 0.230 (P=0.021), 0.356 (P<0.001), and 0.355 (P<0.001), respectively. 99mTc-MAG3 renal scan was correlated with estimated-GFR by all formulas in decreased renal function. CONCLUSION: Estimated GFRs determined using serum creatinine and cystatin C, and 99mTc-MAG3 renal scan correlated well with estimated GFR determined using Ccr. 99mTc-MAG3 renal scan may be replaced for evaluation of renal function with convenience in patients with renal disease and decreased renal function in childhood.

Predicción de sobrevida del injerto a corto y largo plazo mediante el uso de índices gamagráficos en receptores de trasplante renal / Prediction of short and long term graft survival by 99mTc-MAG3 scintigraphy after renal transplantation

Background: 99Tcm-MAG3 is a non-invasive method for the evaluation of renal transplants, giving information about allograft function and short- and long-term allograft survival. However, few studies have validated this observation. Objetive: To determine the predictive power of different scintigraphic parameters on graft survival at 6 -12 months after renal transplantation. Methods: Between 1996-2007, receptors with varying degrees of kidney dysfunction were studied with 99mTc-MAG3 scintigraphy within 14 days after transplantation. Tubular injury score (TISS) ranging I-VI according to severity and renal extraction index (R20/3) were calculated. Survival analysis and Cox regression were used for analysis. Results: Three-hundred and four renograms were performed in 146 allografts (143 receptors, mean age 38.9 +/- 17 years, 81.5 percent from cadaveric donor). Mean follow-up time was 44 months. There was graft loss (GL) in 32 percent renal trasplants. According to severity range, graft survival at 6 and 12 months was: TISS I-II 85.23 percent and 81.17 percent; TISS III-IV 82.43 percent and 80.56 percent, and TISS V-VI 32 percent and 2.,43 percent respectively. TISS score of V-VI score was an independent predictor for GL (HR = 6.3 CI 95 percent 2.9–13; p<0.0001). R20/3 index was not a good predictor of GL. Conclusions: TISS score was an independent predictor of short- and long-term allograft survival using 99mTc-MAG3 scintigraphy performed early after kidney transplantation in patients with suspected patients renal dysfunction. TISS V-VI had a greater discriminatory power. R20/3 index individually did not present a good prognostic performance.

Reflux Nephropathy Detected by Post-voiding Image on Scintigraphic Tc-99m MAG3 Scan

99mTc-MAG3 Scintigraphic Scan is sensitive at depicting focal parenchymal abnormalities and can be used for the measurement of overall renal function. We experienced a 12-year-old girl presenting with fever and flank pain. On the ultrasonogram and post-voiding delayed image of 99mTc-MAG3 scintigraphic scan, severe right cortical atrophy and hydronephrosis with vesicoureteral reflux were detected. We could demonstrate the reflux nephropathy by these two diagnostic work-up without conventional voiding cystourethrography.

Development of Program for Renal Function Study with Quantification Analysis of Nuclear Medicine Image / 대한핵의학회잡지

PURPOSE: In this study, we developed a new software tool for the analysis of renal scintigraphy which can be modified more easily by a user who needs to study new clinical applications, and the appropriateness of the results from our program was studied. MATERIALS AND METHODS: The analysis tool was programmed with IDL5.2 and designed for use on a personal computer running Windows. For testing the developed tool and studying the appropriateness of the calculated glomerular filtration rate (GFR), 99mTc-DTPA was administered to 10 adults in normal condition. In order to study the appropriateness of the calculated mean transit time (MTT), 99mTc-DTPA and 99mTc-MAG3 were administered to 11 adults in normal condition and 22 kidneys were analyzed. All the images were acquired with ORBITOR, the Siemens gamma camera. RESULTS: With the developed tool, we could show dynamic renal images and time activity curve (TAC) in each ROI and calculate clinical parameters of renal function. The results calculated by the developed tool were not different statistically from the results obtained by the Siemens application program (Tmax: p=0.68, Relative Renal Function: p=1.0, GFR: p=0.25) and the developed program proved reasonable. The MTT calculation tool proved to be reasonable by the evaluation of the influence of hydration status on MTT. CONCLUSION: We have obtained reasonable clinical parameters for the evaluation of renal function with the software tool developed in this study. The developed tool could prove more practical than conventional, commercial programs.

Utility of 99mTc-MAG3 Perfusion Indices in the Evaluation of Renal Transplant Function During Early Post-transplantation Period / 대한핵의학회잡지

PURPOSE: We have examined the utility of 99mTc-MAG3 perfusion indices for assessing renal graft function in early post-transplantation period. MATERIALS AND METHODS: Our study included 80 renal transplant recipients (48 men and 32 women, mean age: 40.3 years). Diagnosis was based on biopsy, laboratory data and clinical course. Renal scintigraphy (RS) was obtained using 100 MBq of 99mTc-MAG3 from 11 days to 23 days of kidney transplantation. We measured 5 indices in whole-kidney (WK) and cortical (C) renograms; Hilson's perfusion index (PI), transplant perfusion index (TP) and transplant function index (TF) as perfusion parameter, and the time to peak activity (Tmax) and the ratio of renal counts at 20 min to that at 3 min (K20/3) as functional parameter. RESULTS: The diagnoses at the day of RS were normal graft (NG) in 44, acute rejection (AR) in 14, acute tubular necrosis (ATN) in 10, and Cyclosporine A nephrotoxicity (CsA) in 12. TP and TF were significantly decreased in AR, ATN and CsA, compared to those in NG. K20/3 of AR and ATN were significantly greater than that of NG. WK-Tmax of AR was significantly longer than that of NG. K20/3 of AR and C-K20/3 of ATN were significantly prolonged relative to those of CsA. There were no statistically significant perfusion indices among complication groups. CONCLUSION: TP and TF reflecting microperfusion and initial tubular extraction are reliable in assessing graft function. However, it is required to correlate perfusion indices with functional indices and clinical course in differentiating from one another among complication groups.

Study of Pharmacokinetic Properties for ~(99m)Tc-MAG_3-ASON / 重庆医科大学学报

Objective: To study the pharmacokinetic properties of 99mTc-labeled chelic polymer of MAG3-ASON.Methods: Chelic polymer of 99mTc-MAG3-ASON was prepared according to former methods.Subsequently,this chelic polymer change of concentration was determined by radioactivity counts per minute(CPM),and its half-life of distribution(T1/2?),the half-life of elimination(T1/2?),the central compartment volume of distribution(Vc),the total apparent volume of distribution(Vd) and the total rate of clearance(CL) were calculated by means of 3P97 software.Finally,its rate of binding to serum protein was measured by trichloroacetic acid precipitation.Results: The T1/2?,the T1/2?,the Vc,the Vd and the CL were 2.11min,95.19min,114.9ml,2430.8ml and 17.7ml/min,respectively.After being incubated with fresh human serum for 1.5h,its rate of binding to serum protein was 11.82%.Conclusion: The process of transportation for chelic polymer of 99mTc-MAG3-ASON in vivo is consistent with two-compartment model and it has desirable pharmacokinetic properties.Therefore,it may be used for diagnostic imaging and therapy of cancer.